Method and apparatus for radar infrastructure

ABSTRACT

Examples disclosed herein relate to a radar warning system positioned in a highway infrastructure. The infrastructure element includes a radar unit that is configured to produce radar data from one or more return radio frequency (RF) beams reflected from a surrounding environment using one or more steerable RF beams radiated to the surrounding environment, detect a moving object in a path of the surrounding environment from the radar data, determine whether the moving object in the path is violating directional criteria, and generate an alert message notifying one or more receiving units to avoid the path of the moving object when the moving object in the path is violating the directional criteria. The infrastructure element also includes a communication unit coupled to the radar unit and configured to send the alert message to the one or more receiving units in the surrounding environment.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. Provisional Application No.62/724,172, filed on Aug. 29, 2018, and incorporated by reference in itsentirety.

BACKGROUND

A highway system provides drivers with high speed access togeographically dispersed areas at the risk of high-speed traffic withmany other commuters. The system runs smoothly when drivers followtraffic rules and drive in proper designated lanes. Accidents oftenoccur when a driver is not obeying the rules, such as when a driver isunder the influence of drugs or alcohol or when a driver takes a wrongturn due to bad weather and low visibility. There are a variety ofsituations that result when a vehicle is traveling on the wrong side ofa road or highway. The ability to identify these situations and providea warning or alert to other drivers would reduce the loss of life anddamage from these unfortunate occurrences.

BRIEF DESCRIPTION OF THE DRAWINGS

The present application may be more fully appreciated in connection withthe following detailed description taken in conjunction with theaccompanying drawings, which are not drawn to scale and in which likereference characters refer to like parts throughout, and wherein:

FIG. 1 illustrates a driving environment incorporating a warning systemfor detecting a traffic hazard, according to various implementations ofthe subject technology;

FIG. 2 conceptually illustrates a traffic hazard in the drivingenvironment of FIG. 1, according to various implementations of thesubject technology;

FIG. 3 illustrates a complex of roadways and entrances to a highwayincluding infrastructure elements, according to various implementationsof the subject technology;

FIG. 4 illustrates a vehicle control system and an infrastructure radarsystem, according to various implementations of the subject technology;

FIG. 5 illustrates a flowchart of an example process of operating aninfrastructure radar system, according to various implementations of thesubject technology;

FIG. 6 illustrates a transceiver in a radar unit, according to variousimplementations of the subject technology;

FIG. 7 illustrates a flowchart of an example process of detecting adirectional violation as a function of velocity, according to variousimplementations of the subject technology;

FIG. 8 conceptually illustrates a vehicle acting as a mobileinfrastructure element, according to various implementations of thesubject technology; and

FIG. 9 illustrates a schematic diagram of a packet format for acommunication protocol for a vehicular warning system, according tovarious implementations of the subject technology.

DETAILED DESCRIPTION

The present disclosure provides methods and apparatuses to detectdriving violations and send a control signal warning drivers andalerting authorities. There are many applications for these solutions,and some implementations of the disclosure are illustrated in a radarsystem positioned within a driving environment and may be positioned ina stationary infrastructure or in a vehicle associated with a network ofvehicles.

The subject technology supports autonomous driving with improved sensorperformance, all-weather/all-condition detection, advanceddecision-making algorithms and interaction with other sensors throughsensor fusion. These configurations optimize the use of radar sensors,as radar is not inhibited by weather conditions in many applications,such as for self-driving cars. The ability to capture environmentalinformation early aids control of a vehicle, allowing anticipation ofhazards and changing conditions. The sensor performance is also enhancedwith these structures, enabling long-range and short-range visibility tothe controller. In an automotive application, short-range is consideredwithin 30 meters of a vehicle, such as to detect a person in a crosswalk directly in front of the vehicle; and long-range is considered tobe 250 meters or more, such as to detect approaching cars on a highway.The present disclosure provides for automotive radar sensors capable ofreconstructing the world around them and are effectively a radar“digital eye,” having true 3D vision and capable of human-likeinterpretation of the world.

The subject technology is applicable in wireless communication and radarapplications, and in particular those incorporating meta-structurescapable of manipulating electromagnetic (EM) waves using engineeredradiating structures. For example, the present disclosure provides forantenna structures having meta-structure elements and arrays. Ameta-structure (MTS), as generally defined herein, is an engineered,non- or semi-periodic structure that is spatially distributed to meet aspecific phase and frequency distribution. In some implementations, themeta-structures include metamaterials. There are structures andconfigurations within a feed network to the metamaterial elements thatincrease performance of the antenna structures in many applications,including vehicular radar modules. Additionally, the present disclosuresprovide methods and apparatuses for generating wireless signals, such asradar signals, having improved directivity and reduced undesiredradiation patterns aspects, such as side lobes. The present disclosuresprovide antennas with unprecedented capability of generating RF wavesfor radar systems. The present disclosure provides improved sensorcapability and support autonomous driving by providing one of thesensors used for object detection. The present disclosure is not limitedto these applications and may be readily employed in other antennaapplications, such as wireless communications, 5G cellular, fixedwireless and so forth.

The detailed description set forth below is intended as a description ofvarious configurations of the subject technology and is not intended torepresent the only configurations in which the subject technology may bepracticed. The appended drawings are incorporated herein and constitutea part of the detailed description. The detailed description includesspecific details for the purpose of providing a thorough understandingof the subject technology. However, the subject technology is notlimited to the specific details set forth herein and may be practicedusing one or more implementations. In one or more instances, structuresand components are shown in block diagram form in order to avoidobscuring the concepts of the subject technology. In other instances,well-known methods and structures may not be described in detail toavoid unnecessarily obscuring the description of the examples. Also, theexamples may be used in combination with each other.

FIG. 1 illustrates a driving environment 100 incorporating a warningsystem for detecting a traffic hazard, according to variousimplementations of the subject technology. The driving environment 100includes a roadway 102 that has multiple lanes, namely a first lane102-1 and a second lane 102-2. For example, the first lane 102-1 carriestraffic moving right-to-left and the second lane 102-2 carries trafficmoving left-to-right. The driving environment 100 includes aninfrastructure element 140 positioned proximate to the roadway 102. Theinfrastructure element 140 may be a roadway sign mounted to one or morevertical poles, an overpass structure that extends over one or morelanes of the roadway 102, a bridge, or the like. In some aspects, theinfrastructure element 140 is positioned at a side of a road or highway,such as on a shoulder next to the roadway 102. In other aspects, theinfrastructure element 140 is positioned over and above the roadway 102.

The infrastructure element 140 includes a radar unit (not shown) thatcan emit EM radiation toward the roadway 102 to scan a proximate area ofthe roadway 102 and detect stationary and moving objects, and morespecifically, to identify vehicles traveling opposite to the designateddirection of travel. The radar unit detects a moving vehicle as afunction of the velocity of the vehicle.

The radar signal uses a modulation scheme that enables determination ofthe vehicle's velocity and location, such as by a modulated transmittersignal. In some aspects, the radar unit can generate a specifictransmission signal, such as a Frequency Modulated Continuous Wave(FMCW) signal, which is used for radar sensor applications as thetransmitted signal is modulated in frequency, or phase. The FMCW signalenables radar to measure range to an object by measuring the phasedifferences in phase or frequency between the transmitted signal and thereceived signal, or reflected signal. Other modulation types may beincorporated according to the desired information and specifications ofa system and application. Within FMCW formats, there are a variety ofmodulation patterns that may be used within FMCW, including sinusoidal,triangular, sawtooth, rectangular and so forth, each having advantagesand purposes. For example, sawtooth modulation may be used for largedistances to a target; a triangular modulation enables use of theDoppler frequency, and so forth.

As depicted in FIG. 1, vehicles 110 and 130 are traveling in oppositedirections on their respective lanes 102-1 and 102-2. In some aspects, apolice car 120 is in a stationary position proximate to the roadway 102.Each of the vehicles, namely the vehicles 110, 130 and the police car120, may include a communications module that is configured to receive acommunication signal from the infrastructure element 140. Thecommunication signal may include one or more messages relating to atraffic hazard or emergency condition on the roadway 102. In thisrespect, the vehicle 110 may receive a message indicating the locationof the vehicle 130 and the traffic condition of the roadway 102, andconversely, the vehicle 130 may receive a similar message indicating thelocation of vehicle 110 including the traffic condition. The police car120 may receive a message indicating the locations of vehicles 110, 130and the traffic condition of the roadway 102. The traffic conditionincluded in the message may indicate the velocity of a vehicle relativeto the infrastructure element 140, such as a compliant velocity or anon-compliant velocity. In some aspects, the Doppler shift is negativefor a target moving away from a radar unit, and the Doppler shift ispositive for a target moving toward the radar unit. In this respect, amoving object may have a compliant velocity or a non-compliant velocitydepending on the expected Doppler shift. In some implementations, if theexpected Doppler shift is positive, a compliant velocity indicatesproper compliance with traffic rules, and a non-compliant velocityindicates a violation of the traffic rules. As used herein, the term“compliant velocity” may refer to “non-negative velocity,” and the term“non-compliant velocity” may refer to “negative velocity.” The velocityserves as a directional indicator and may be considered a binarydecision. The expected Doppler shift may vary depending on which trafficlane of a roadway the radar unit is detecting and its expecteddirectional criteria.

FIG. 2 conceptually illustrates a traffic hazard in a drivingenvironment 200, according to various implementations of the subjecttechnology. As illustrated in FIG. 2, the driving environment 200includes a roadway 202 that has multiple lanes, namely a first lane202-1 and a second lane 202-2. For example, the first lane 202-1 carriestraffic moving right-to-left and the second lane 202-2 carries trafficmoving left-to-right. The driving environment 200 includes aninfrastructure element 240 positioned proximate to the roadway 202. Theinfrastructure element 240 includes a radar unit 242 and a communicationunit 244.

In various examples, vehicles 210 and 280 are traveling on separatelanes (e.g., lanes 202-1, 202-2) in opposite directions of the roadway202. The scenario of FIG. 2 conceptually illustrates a traffic hazard,where at least one vehicle is traveling in a wrong direction. Forexample, vehicle 290 is traveling on a same lane as that of vehicle 210,namely lane 202-1, and in opposite directions. In this respect, vehicle290 is on a collision course with vehicle 210.

In various examples, the vehicle 210 is an autonomous vehicle havingmultiple perception sensors capable of capturing real-world perceptiondata about its path and surrounding environment, including radar, lidar,camera, and so forth. Each one of the perception sensors may havedifferent range and resolution capabilities. As illustrated in FIG. 2,the vehicle 210 includes a radar unit 220, among others. The vehicle 210may include a sensor fusion module (not shown) that combines data fromdifferent perception sensors in the vehicle 210 and data received fromperception sensors in other geographically disparate autonomous vehiclesincluding infrastructure elements to perceive its environment moreaccurately and enhance target detection and identification. Thisinformation may include information such as congestion on a highway,road conditions, and other conditions that would impact the sensors,actions or operations of the vehicle. As used herein, the term“autonomous vehicle” may refer to an autonomous transport machine fortransporting one or more passengers independent of any, if not at leastpartial, control by any one of the passengers.

In some implementations, the radar unit 220 can provide a 360° true 3Dvision and human-like interpretation of the surrounding environment. Theradar unit 220 is capable of shaping and steering radio frequency (“RF”)beams in all directions in a 360° field-of-view (“FoV”) and recognizingtargets quickly with a high degree of accuracy over a short range ofaround 300 meters or less and over a long range of around 300 meters ormore. Target detection and identification by the vehicle 210 is alsoenhanced with the sensor fusion module using data received from aninfrastructure element, such as the infrastructure element 240.

In operation, the radar unit 242 generates and transmits FMCW radarsignals and receives echoes or reflections from objects in the drivingenvironment 200. The radar unit 242 can detect vehicles traveling in awrong direction, such as vehicle 290. The ability to detect such vehicleoperation enables the infrastructure element 240 to warn other driversand vehicles on the roadway 202. The infrastructure radar system 242communicates with vehicles within the driving environment 200, such asvehicle 210 having a communication unit 222 positioned within. In someaspects, the communication unit 244 and the communication unit 222communicate via a wireless communication network, such as 5G cellularnetwork, and/or a wireless communication protocol, such as Wireless LAN(IEEE 802.11) or Bluetooth (IEEE 802.15). The communication unit 222receives a warning indicator from the infrastructure element 240 when anemergency situation is identified. For example, vehicle 210 may receiveinformation from the infrastructure element indicating travelinginformation about the vehicle 290 (e.g., direction, velocity, distancefrom vehicle 210, roadway lane, or the like). In some aspects, theinformation includes radar data obtained by the infrastructure element240 that the vehicle 210 can process with its sensor fusion module. Suchwarning enables vehicle 210 to steer out of the way of an on-comingvehicle (e.g., vehicle 290), and enables vehicle 280 to reduce itsvelocity or continue traveling while out of the way of vehicle 290.

In some implementations, other infrastructure elements, such asinfrastructure element 230, may also include a radar and communicationunit (not shown). The infrastructure elements 240, 230 are positioned toprovide maximum radar coverage of the roadway 202. In some aspects, theinfrastructure element 240 may communicate with the infrastructureelement 230 via the communication unit 244. In this respect, theinfrastructure elements 230 and 240 may exchange messages and/or radardata with respect to received reflections from the roadway 202. In otheraspects, the infrastructure element 230 may communicate with vehiclestraveling on the roadway 202, including the vehicle 210.

FIG. 3 illustrates a complex of roadways and entrances to a highwayincluding infrastructure elements, according to various implementationsof the subject technology. The infrastructure elements can serve aslocations, where an infrastructure radar unit 372 may be positioned. Acomplex configuration of radar units in infrastructure elements enablescommunication of signals and warnings throughout a driving environment.The radar units are positioned on or within infrastructure elements, andthe infrastructure elements may be positioned on overpasses, buildings,bridges and so forth. The infrastructure elements with the radar unitsmay be positioned at entries to highways, such as entry ramp 370, toidentify a vehicle traveling in the wrong direction and provide advancenotice to other vehicles traveling along the same path as early aspossible.

The infrastructure radar unit 372 includes an antenna 376, a transceivermodule 378 and an antenna controller 374. The antenna 376 can radiatedynamically controllable and highly-directive RF beams usingmeta-structures. In some implementations, the meta-structures includemetamaterials. The transceiver module 378 is coupled to the antenna 376,and prepares a signal for transmission, such as a signal for a radardevice. In some aspects, the signal is defined by modulation andfrequency. The signal is provided to the antenna 376 through a coaxialcable or other connector and propagates through the antenna structurefor transmission through the air via RF beams at a given phase,direction, and so on. The RF beams and their parameters (e.g., beamwidth, phase, azimuth and elevation angles, etc.) are controlled byantenna controller 374.

The RF beams reflect from targets in the surrounding environment, andthe RF reflections are received by the transceiver module 378. Radardata from the received RF beams is provided to a perception engine (notshown) for target detection and identification. The radar data may beorganized in sets of Range-Doppler (RD) map information, correspondingto four-dimensional (4D) information that is determined by each RF beamreflected from targets, such as azimuthal angles, elevation angles,range, and velocity. The RD maps may be extracted from FMCW radarsignals and may contain both noise and systematic artifacts from Fourieranalysis of the radar signals. The perception engine may control furtheroperation of the infrastructure radar unit 372 by, for example,providing an antenna control signal containing beam parameters for thenext RF beams to be radiated from the cells in the antenna 376.

In operation, the antenna controller 374 is responsible for directingthe antenna 376 to generate RF beams with determined parameters such asbeam width, transmit angle, and so on. The antenna controller 374 may,for example, determine the parameters at the direction of the perceptionengine, which may at any given time determine to focus on a specificarea of an FoV upon identifying targets of interest in the surroundingenvironment. The antenna controller 374 determines the direction, power,and other parameters of the RF beams and controls the antenna 376 toachieve beam steering in various directions within a scan angular range371. The antenna controller 374 also determines a voltage matrix toapply to phase shifter elements coupled to the antenna 376 to achieve agiven phase shift. In some examples, the antenna 376 is adapted totransmit a directional beam through active control of the reactanceparameters of the individual cells that make up the antenna 376. Next,the antenna 376 radiates RF beams having the determined parameterswithin the scan angular range 371. The RF beams are reflected fromtargets in and around the surrounding environment (e.g., in a 360° fieldof view) and are received by the transceiver module 378 ininfrastructure radar unit 372.

In some implementations, the complex of roadways may include a networkof infrastructure radar units, where each radar unit may communicatewith other radar units of the network. In some aspects, the networkincludes a mesh network of radar units. The network of infrastructureradar units includes infrastructure radar units 372, 382, 384, and 386.The infrastructure radar units 372, 382, 384, and 386 may be located inseparate infrastructure elements. In some implementations, theinfrastructure radar units 372, 382, 384, and 386 may communicate withone another through one or more wireless communication protocols, suchas wireless LAN (IEEE 802.11), cellular 5G, Bluetooth (IEEE 802.15),ad-hoc network such as a vehicle-to-vehicle (V2V) communication networkor vehicle-to-everything (V2X) communication network, a Dedicated ShortRange Communication (DSRC) network, a Wireless Access in VehicularEnvironment (WAVE) network, or the like.

FIG. 4 illustrates a schematic diagram of a vehicle control system 400and an infrastructure radar system 442, according to variousimplementations of the subject technology. Not all of the depictedcomponents may be used, however, and one or more implementations mayinclude additional components not shown in the figure. Variations in thearrangement and type of the components may be made without departingfrom the scope of the claims set forth herein. Additional components,different components, or fewer components may be provided.

The vehicle control system 400 includes a communication unit 418, avehicle state and map unit 420, and a central processing unit 430. Thecentral processing unit 430 can process data exchanged between thecommunication unit 418 and the vehicle state and map unit 420. Thecommunication unit 418 includes sensing modules 432, controllers 434,emergency control 436, sensor fusion 438, and a communication module440. The sensing modules 432 can determine objects in an environment.The sensor fusion 438 can combine information from various sensors onthe vehicle and determine actions that are implemented by thecontrollers 434. The communication module 440 can receive communicationsfrom the infrastructure radar system 442 and send this information tothe emergency control 436, which then sends signals to the controllers434.

The vehicle state and map unit 420 includes a set of state informationmodules, including operational state module 422, a vehicle state module424, an environment state module 426 and a control map 428. Theoperational state module 422 can describe the current operational modeof a vehicle (e.g., vehicle 110). The vehicle state module 424 indicatesthe parameters defining such operation of the vehicle. The environmentstate module 426 indicates the objects in the environment and thevelocity of these objects. The control map 428 can map indicator signalsto control actions, such as when a warning signal is received frominfrastructure element(s), and the signal is mapped to a preventativeaction such as to warn the driver or direct the vehicle to change itstravel path and steer the vehicle away from danger.

The infrastructure radar system 442 includes a radar unit 444, avelocity compare module 446, an action map 448, a communication module450, and a central processing unit 452. The radar unit 444 may includean antenna module (not shown) that provides dynamically controllable andsteerable beams that can focus on one or multiple portions of a 360° FoVof the vehicle. The beams radiated from the antenna module are reflectedfrom targets in the surrounding environment and received and processedby the radar unit 444 to detect and identify the targets. The radar unit444 may include a perception module (not shown) that is trained todetect and identify targets and control the antenna module as desired.The velocity compare module 446 can perform a comparison between thedetected velocity of a vehicle and a predetermined threshold todetermine whether the detected vehicle velocity is a non-negativevelocity or a negative velocity. In some aspects, the velocity comparemodule 446 may compare the detected velocity to multiple thresholds. Inother aspects, the velocity compare module 446 may compare the detectedvelocity to a threshold that corresponds to a highest prioritypreventative action. In this respect, the radar unit 444 may issue analert message without the need to confirm the velocity of the vehiclegiven that the detected velocity may have exceeded a high velocitythreshold. The action map 448 can determine an action corresponding tovelocity measures of an object. In some aspects, the action map 448 mayinclude multiple actions mapped to different thresholds that correspondto respective velocities. The communication module 450 can receivecommunications from the vehicle control system 400. In some aspects,modules and systems in the infrastructure radar system 442 communicatewith each other through the communication module 450.

FIG. 5 illustrates a flowchart of an example process 500 of operating aninfrastructure radar system, according to various implementations of thesubject technology. For explanatory purposes, the example process 500 isprimarily described herein with reference to the radar unit 444 of FIG.4; however, the example process 500 is not limited to the radar unit 444of FIG. 4, and the example process 500 can be performed by one or moreother components of the radar unit 444 of FIG. 4 or from a mobilenetwork element, such as a vehicle. Further for explanatory purposes,the blocks of the example process 500 are described herein as occurringin series, or linearly. However, multiple blocks of the example process500 can occur in parallel. In addition, the blocks of the exampleprocess 500 can be performed in a different order than the order shownand/or one or more of the blocks of the example process 500 may not beperformed.

The process 500 begins at step 502, where the radar unit 444 of aninfrastructure element (e.g., infrastructure element 140, 240) receivesa radar echo signal and obtains a velocity measurement of a detectedvehicle from the received radar echo signal. Next, at step 504, theradar unit 444 determines whether the velocity measurement is lesserthan zero. If the velocity measurement is negative (or less than zero),or within a first velocity range, the process 500 proceeds to step 506.Otherwise, the process 500 returns to step 502 to receive a new radarecho signal. At step 506, the radar unit 444 sends a control signal atlevel 1. In some aspects, the control signal sent at step 506 may bereferred to as an alert message of a first priority. This signal may beas described in FIG. 9 or may be otherwise configured to alert othervehicles in the area as quickly as possible. Subsequently, at step 508,the radar unit 444 confirms whether the velocity measurement is lesserthan zero, or within the first range. If the velocity is less than zero,the process 500 proceeds to step 510. Otherwise, the process 500proceeds back to step 502. In some aspects, the step 508 is performed toconfirm whether the detected object is indeed a moving vehicle or anobject other than a vehicle (e.g., a person) moving at a relatively slowvelocity. At step 510, the radar unit 444 confirms the reverse directionof a vehicle by verifying its velocity is less than zero, or within thefirst range. Next, at step 512, the radar unit 444 sends a controlsignal at level 2, which is a heightened emergency indicator. In someaspects, the control signal sent at step 512 may be referred to as analert message of a second priority greater than the first priority.Subsequently, at step 514, the information is reported to a maincontroller to determine a next action. In some implementations, thecontrol signal level (Level 1, Level 2) is stored along with a timestamp for comparison to later measurements. In some implementations, acontrol signal with a single level allows the alerted vehicles to makedecisions accordingly. For autonomous vehicles, the control signal mayinclude an action for the alerted vehicle to take or the control signalmay trigger an aversion process within the autonomous vehicle.

FIG. 6 illustrates a transceiver 600 in a radar unit, according tovarious implementations of the subject technology. Not all of thedepicted components may be used, however, and one or moreimplementations may include additional components not shown in thefigure. Variations in the arrangement and type of the components may bemade without departing from the scope of the claims set forth herein.Additional components, different components, or fewer components may beprovided.

In some implementations, the transceiver 600 may be implemented in aninfrastructure element and/or a vehicle. When positioned within avehicle, the vehicle may act as mobile infrastructure detecting vehiclesmoving against traffic and sending warning signals to emergencypersonnel and/or other vehicles. The transceiver includes a controlinterface 602, a processing unit 604, an information management unit606, a power control unit 612, an object detection unit 616 and anobject recognition unit 624. The transceiver 600 also includes amodulation control unit 640 and a warning sensor 641. The transceiver600 further includes an antenna module 630 controlled by beam controlunit 618, which includes beam forming module 642 and beam steeringmodule 644. In this way, the transceiver 600 enables a vehicle tooperate in a mobile mode similar to operation of the infrastructureelement, whereby the vehicle is able to detect vehicles violatingdirectional rules and alert other vehicles in the vicinity and/or thepath of the violating vehicle.

The processing unit 604 controls the information management unit 606 andthe control interface 602 for communication with other system controls,such as a sensor fusion in a vehicle. The processing unit 604 canprocess data exchanged between the various components of the transceiver600, including the object detection unit 616, beam control unit 618 andthe antenna module 630, among others. The power control unit 612 cancontrol the power supplies in the transceiver 600 by controlling theamount of voltage supplied to each of the components in the transceiver600. The power control unit 612 may control the amount of bias suppliedto the modulation control unit 640 and to the beam control unit 618 forfacilitating the beam steering operation of the transceiver 600.Communication within the transceiver 600 may be transmitted through thecommunication module 610. In some aspects, modules and systems in thetransceiver 600 communicate with each other through the communicationmodule 610.

The object recognition unit 624 can receive analog data from theantennas and/or the processed data of location, velocity and so forth,and determines an object type therefrom. In some implementations, theobject recognition unit 624 includes one or more neural network (NN)processors, such as a convolutional NN (CNN) that trains on known datato match received data to images or object types. The object detectionunit 616 includes a Doppler process unit 617. The Doppler process unit617 uses the received reflection from an object or target to determine alocation, velocity and other parameters of the object. This may be doneby use of an FMCW signal having a sawtooth, triangular or other waveform.

In some implementations, the object recognition unit 624 works withobject detection unit 616 for more clarity as to the object, and thewarning sensor 641 determines if any objects are moving directly towardthe vehicle having the transceiver. For example, the object detectionunit 616 may detect a vehicle traveling in the wrong direction anddirect the antenna module 630, at the instruction of the beam controlunit 618, to focus additional RF beams at a given phase shift anddirection within the portion of the FoV corresponding to the location ofthe detected vehicle.

The object detection unit 616 may also include a moving object tracker(not shown) to track the identified objects over time, such as, forexample, with the use of a Kalman filter. The moving object trackermatches candidate targets identified by the object recognition unit 624with targets it has detected in previous time windows. By combininginformation from previous measurements, expected measurementuncertainties, and some physical knowledge, the moving object trackercan generate robust, accurate estimates of moving vehicle locations.

The doppler process unit 617 takes a series of RD maps from the antennamodule 630 and extracts a doppler signal from them. The doppler signalenables a more accurate identification of targets as it providesinformation on the occupancy of a target in various directions overtime. In this respect, the doppler signal can indicate the change inphase at respective locations of the moving vehicle such that a negativevelocity determination can be performed by the objection detection unit616.

Information on identified vehicles over time are then stored in theenvironment profile 622, which keeps track of targets' locations andtheir movement over time as determined by the moving object tracker. Thetracking information provided by the moving object tracker and thedoppler signal provided by the doppler process unit 617 are combined atthe environment profile 620 to produce an output containing thetype/class of target identified, their location, their velocity, and soon.

The warning sensor 641 may receive an indication from an infrastructureradar unit or may receive a radar echo indicating a moving objectviolates the directional rules of the road. The warning sensor 641 maycapture the velocity and/or acceleration from the modulated signal andthen compare one or both to directional rules. When a violation isfound, the warning sensor 641 may also determine a radar cross-sectionalarea to verify that the moving object is a vehicle. In this way, thevehicle can determine imminent danger in its environment by one or moremethods and take corrective action to avoid a collision. The correctiveaction may be provided to a human driver or may be implemented by anautonomous system that can respond quickly and according topredetermined rules. These rules may update as the vehicle drives toenhance the safety mechanism. Similarly, the transceiver 600 enables avehicle to become an impromptu real-time radar infrastructure element toidentify dangerous conditions on the highway. The vehicle may transmitan alert to other vehicles and to infrastructure elements, includingradar infrastructure elements, cellular systems, wireless networks othervehicles, and so forth.

The transceiver 600 also includes a communication module 610, a soundingsignal control module 620 and an environment profile 622. The soundingsignal control unit 620 is coupled to antenna module 630. The soundingsignal control module 620 includes circuitry for generating andtransmitting a sounding signal that is added to such a system to provideadditional information and assist the vehicle system to create a realtime landscape. The information is processed to create the environmentprofile 622. The environment profile 622 may include environmental datafrom detections of various conditions in the surrounding environment,such as temperature, humidity, fog, visibility, precipitation, amongothers. The antenna module 630 is coupled to the modulation control unit640 and the object detection unit 616 having a doppler process unit 617to extract reflection information from modulated signals. The modulationcontrol unit 640 can control the type of modulation applied to atransmit signal. In some aspects, the transmit signal may be modulatedin frequency or phase.

The transceiver 600 also includes a memory storage unit 608 for storingone or more both of volatile memory data and non-volatile memory data.The memory storage unit 608 can store useful data for the radar unit,such as, for example, information on which subarrays and/or elements ofthe antenna module 630 perform better under different conditions. Thememory storage unit 608 may store information and data (e.g., static anddynamic data) used for operation of the transceiver 600.

In operation, the antenna module 630 scans an environment around avehicle, in which reflected signals provide indications of positions andvelocity, as well as other characteristics of objects. This creates aradar system for enabling the vehicle to understand its surroundings.

FIG. 7 illustrates a flowchart of an example process 700 of detecting adirectional violation as a function of velocity, according to variousimplementations of the subject technology. For explanatory purposes, theexample process 700 is primarily described herein with reference to theradar unit 444 of FIG. 4; however, the example process 700 is notlimited to the radar unit 444 of FIG. 4, and the example process 700 canbe performed by one or more other components of the radar unit 444 ofFIG. 4 or from a mobile network element, such as a vehicle. Further forexplanatory purposes, the blocks of the example process 700 aredescribed herein as occurring in series, or linearly. However, multipleblocks of the example process 700 can occur in parallel. In addition,the blocks of the example process 700 can be performed in a differentorder than the order shown and/or one or more of the blocks of theexample process 700 may not be performed.

In some implementations, the process 700 can be used to evaluate a radarecho at an infrastructure element (e.g., 140). The process 700 starts atstep 702, where the radar unit 444 in an infrastructure element receivesEM reflections. Next, at step 704, the radar unit 444 extracts velocityinformation as a function of a modulation signal associated with thereceived EM reflections. Subsequently, at step 706, the radar unit 444applies directional criteria to determine a direction of vehiclestraveling in the vicinity. Next, at step 708, the radar unit 444determines whether the velocity violates the directional criteria. Ifthe velocity is determined as violating the directional criteria, thenthe process 700 proceeds to step 710. Otherwise, the process 700 returnsto step 702 to receive new EM reflections. At step 710, thecommunication module 450 in the radar unit 444 sends a communicationsignal to a vehicle that triggers or prompts the vehicle to execute afirst action. Subsequently, at step 712, the radar unit 444 stores anemergency status condition and associated time stamp in a memory (e.g.,608). Next, at step 714, the radar unit 444 of the infrastructureelement receives further EM reflections to confirm the emergency status.The infrastructure element may receive the further EM reflections inresponse to additional chirp signals transmitted by the radar unit ofthe infrastructure element. The operation at step 714 may be triggeredby the need to confirm whether the detected object is indeed a movingvehicle or a person (or other non-vehicle object) moving at a relativelylow velocity. Subsequently, at step 716, the radar unit 444 confirmswhether the directional criteria has been violated. If the directionalcriteria violation is confirmed, the process 700 proceeds to step 718.At step 718, the transceiver (e.g., 600) of the radar unit 444 sends acommunication signal that instructs the receiving vehicle to execute anemergency action. Otherwise, the process 700 proceeds to step 720, wherethe transceiver (e.g., 600) of the radar unit 444 sends a cancellationmessage to the receiving vehicle to cancel (or withdraw) execution ofthe first action, when the directional criteria violation is notconfirmed.

FIG. 8 conceptually illustrates a vehicle 880 acting as a mobileinfrastructure element, according to various implementations of thesubject technology. The vehicle 880 includes a radar unit 843 and acommunication unit 841. The radar unit 843 is adapted to identifyvehicles that violate directional road rules, such as vehicle 890, whichis traveling on the wrong side of the highway and is directed intoon-coming traffic, such as vehicle 810. The vehicle 880 detects vehicle890 by comparing the received radar echoes to directional criteria. Oncea violation is identified based at least on the comparison between thereceived radar echoes and the directional criteria, the vehicle 880determines that the detected violation represents a dangerous conditionon the highway and sends an alert to the vehicle 810 by way of thecommunication unit 841. The alert may be sent out as a broadcast signalacross a broad area, or may be sent to specific recipients, such asvehicle 810 through communication unit 820, vehicle 890 and/orinfrastructure element 840 through communication unit 842. For example,the vehicle 880 may be in communication with the vehicle 810 over acommunication channel associated with a wireless communication network(e.g., V2V communication network, cellular 5G, wireless LAN, or thelike). The alert enables drivers, vehicles, emergency personnel and/orinfrastructure to respond to the alert. In some implementations, wherethere is sufficient warning, the highway infrastructure system mayimplement a deterrent, such as spikes in a road or a roadblock. In someaspects, the alert triggers a broadcast message on billboards, wheremessages indicate actions for drivers and alert them to the danger.

FIG. 9 illustrates a schematic diagram of a packet format 900 of acommunication protocol for a vehicular warning system, according tovarious implementations of the subject technology. An alert message, inconnection with alerting other vehicles about an impending trafficemergency on a roadway, may be transmitted in a variety of ways. In someaspects, the alert message is transmitted in accordance with the packetformat 900. The packet format 900 includes various fields forcommunication over one or more communication channels. The packet format900 includes an alert header field 902, an origin field 904, a targetrecipient field 906, a status field 908, a payload 910, a status field912, a payload information field 914, and an alert tail field 916. Notall of the depicted components may be used, however, and one or moreimplementations may include additional components not shown in thefigure. Variations in the arrangement and type of the components may bemade without departing from the scope of the claims set forth herein.Additional components, different components, or fewer components may beprovided.

The alert header field 902 and the alert tail field 916 can identify thebounds of the message. The origin field 904 (or source field) identifiesthe detection point, and the target recipient field 906 may be aspecific infrastructure unit or may indicate a broadcast or multicastcommunication. The status field 908 indicates the condition, which maybe coded to identify an accident, a vehicle traveling the wrong way, andso forth. The payload 910 contains the message (or content) relating tothe alert message. The status field 912 indicates a status of the alertmessage. The payload information field 914 indicates additionalinformation 922, in which such information may include mission criticalservice information, specific instruction or action, general instructionor action, interwork details for legacy systems, interconnectinformation for cellular system, broadcast details, imminent perilcommunication details, location, data streaming information, roaddeterrent and so forth. The protocol and messaging enable an impromptunetwork structure 920 to cover a prescribed area, a large area,complementary areas and so forth.

It is also appreciated that the previous description of the disclosedexamples is provided to enable any person skilled in the art to make oruse the present disclosure. Various modifications to these examples willbe readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other examples withoutdeparting from the spirit or scope of the disclosure. Thus, the presentdisclosure is not intended to be limited to the examples shown hereinbut is to be accorded the widest scope consistent with the principlesand novel features disclosed herein.

As used herein, the phrase “at least one of” preceding a series ofitems, with the terms “and” or “or” to separate any of the items,modifies the list as a whole, rather than each member of the list (i.e.,each item). The phrase “at least one of” does not require selection ofat least one item; rather, the phrase allows a meaning that includes atleast one of any one of the items, and/or at least one of anycombination of the items, and/or at least one of each of the items. Byway of example, the phrases “at least one of A, B, and C” or “at leastone of A, B, or C” each refer to only A, only B, or only C; anycombination of A, B, and C; and/or at least one of each of A, B, and C.

Furthermore, to the extent that the term “include,” “have,” or the likeis used in the description or the claims, such term is intended to beinclusive in a manner similar to the term “comprise” as “comprise” isinterpreted when employed as a transitional word in a claim.

A reference to an element in the singular is not intended to mean “oneand only one” unless specifically stated, but rather “one or more.” Theterm “some” refers to one or more. Underlined and/or italicized headingsand subheadings are used for convenience only, do not limit the subjecttechnology, and are not referred to in connection with theinterpretation of the description of the subject technology. Allstructural and functional equivalents to the elements of the variousconfigurations described throughout this disclosure that are known orlater come to be known to those of ordinary skill in the art areexpressly incorporated herein by reference and intended to beencompassed by the subject technology. Moreover, nothing disclosedherein is intended to be dedicated to the public regardless of whethersuch disclosure is explicitly recited in the above description.

While this specification contains many specifics, these should not beconstrued as limitations on the scope of what may be claimed, but ratheras descriptions of particular implementations of the subject matter.Certain features that are described in this specification in the contextof separate implementations can also be implemented in combination in asingle implementation. Conversely, various features that are describedin the context of a single implementation can also be implemented inmultiple implementations separately or in any suitable sub combination.Moreover, although features may be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination may be directed to a subcombination or variation of a sub combination.

The subject matter of this specification has been described in terms ofparticular aspects, but other aspects can be implemented and are withinthe scope of the following claims. For example, while operations aredepicted in the drawings in a particular order, this should not beunderstood as requiring that such operations be performed in theparticular order shown or in sequential order, or that all illustratedoperations be performed, to achieve desirable results. The actionsrecited in the claims can be performed in a different order and stillachieve desirable results. As one example, the processes depicted in theaccompanying figures do not necessarily require the particular ordershown, or sequential order, to achieve desirable results. Moreover, theseparation of various system components in the aspects described aboveshould not be understood as requiring such separation in all aspects,and it should be understood that the described program components andsystems can generally be integrated together in a single hardwareproduct or packaged into multiple hardware products. Other variationsare within the scope of the following claim.

What is claimed is:
 1. An infrastructure element positioned proximate toa roadway, comprising: a radar unit comprising an antenna module and aperception engine to control beam steering of the antenna module, theradar unit configured to: produce radar data from one or more returnradio frequency (RF) beams reflected from a surrounding environmentusing one or more steerable RF beams radiated from the antenna module tothe surrounding environment, wherein the antenna module is configured todetermine parameters of the one or more steerable RF beams during aguidance of the perception engine and achieves beam steering in variousdirections within a scan angular range; detect a moving object in a pathof the surrounding environment from the radar data with the perceptionengine; determine whether the moving object in the path is violatingdirectional criteria; and generate an alert message notifying one ormore receiving units to avoid the path of the moving object when themoving object in the path is violating the directional criteria; and acommunication unit coupled to the radar unit and configured to send thealert message to the one or more receiving units in the surroundingenvironment.
 2. The infrastructure element of claim 1, wherein the radarunit comprises: a velocity compare module configured to: perform acomparison between a velocity of the detected moving object and apredetermined threshold; determine whether the velocity of the detectedmoving object is a compliant velocity or a non-compliant velocity fromthe comparison; and determine that the moving object is violating thedirectional criteria when the velocity is a negative velocity.
 3. Theinfrastructure element of claim 1, wherein the radar unit is furtherconfigured to: extract the velocity as a function of a modulated signalfrom the radar data; determine whether the extracted velocity is lesserthan zero; and determine that the moving object is violating thedirectional criteria when the extracted velocity is lesser than zero. 4.The infrastructure element of claim 1, wherein the radar unit is furtherconfigured to: obtain a velocity measurement of the moving object fromthe radar data; determine that the velocity measurement does not satisfythe directional criteria; and generate the communication signal with afirst priority that corresponds to a first preventative action.
 5. Theinfrastructure element of claim 4, wherein the radar unit is furtherconfigured to determine that the velocity measurement corresponds to thefirst preventative action from a mapping between a plurality of actionsand velocity measurements of the moving object.
 6. The infrastructureelement of claim 4, wherein the radar unit is further configured to:confirm whether the velocity measurement is lesser than zero, or withinthe first range of velocities; send a second communication signalindicating a second alert message with a second priority different fromthe first priority when the velocity measurement is confirmed, thesecond alert message causing the one or more receiving units to performa second action with more urgency than the first action; and send athird communication signal that instructs the one or more receivingunits to cancel the first action when the velocity measurement is notconfirmed.
 7. A radar system in an infrastructure element, comprising:an antenna module comprising one or more meta-structure antennas thatare configured to radiate one or more transmission radio frequency (RF)beams to a surrounding environment and receive one or more return RFbeams reflected from a moving object in the surrounding environment; aperception engine, wherein the antenna module is configured to determineparameters of the one or more transmission RF beams during a guidance ofthe perception engine; an object detection unit configured to detect themoving object and control beam steering of the antenna module to focuson a specific area of a field of view (FoV) within a scan angular range;a directional criteria evaluation unit configured to extract a velocityof the moving object and determine whether the moving object isviolating directional criteria; and a communication unit coupled to theradar unit and configured to send an alert message to one or morereceiving units in the surrounding environment, the alert messagenotifying the one or more receiving units of a traffic condition statusbased at least on whether the moving object is violating the directionalcriteria.
 8. The radar system of claim 7, further comprising a velocitycompare module configured to: perform a comparison between the velocityof the moving object and a predetermined threshold; determine whetherthe velocity of the detected moving object is a compliant velocity or anon-compliant velocity from the comparison; and determine that themoving object is violating the directional criteria when the velocity isa non-compliant velocity.
 9. The radar system of claim 7, wherein thedirectional criteria evaluation unit is further configured to: determinewhether the velocity is lesser than zero; and determine that the movingobject is violating the directional criteria when the velocity is lesserthan zero.
 10. The radar system of claim 7, wherein the directionalcriteria evaluation unit is further configured to: obtain a velocitymeasurement of the moving object from the radar data; determine that thevelocity measurement does not satisfy the directional criteria; andgenerate the communication signal with a first priority that correspondsto the first preventative action.
 11. The radar system of claim 10,wherein the directional criteria evaluation unit is further configuredto determine that the velocity measurement is lesser than zero based atleast on a comparison to the directional criteria.
 12. The radar systemof claim 10, wherein the directional criteria evaluation unit is furtherconfigured to determine that the velocity measurement is not within afirst range of velocities based at least on a comparison to thedirectional criteria, the first range of velocities comprising compliantvelocities.
 13. The radar system of claim 10, wherein the directionalcriteria evaluation unit is further configured to determine that thevelocity measurement corresponds to the first action from a mappingbetween a plurality of actions and velocity measurements of the movingobject.
 14. The radar system of claim 10, wherein the directionalcriteria evaluation unit is further configured to: confirm whether thevelocity measurement is lesser than zero, or within the first range ofvelocities; send a second communication signal indicating a second alertmessage with a second priority different from the first priority whenthe velocity measurement is confirmed, the second alert message causingthe one or more receiving units to perform a second action with moreurgency than the first action; and send a third communication signalthat instructs the one or more receiving units to cancel the firstaction when the velocity measurement is not confirmed.
 15. A method ofoperating a radar system in an infrastructure element, the methodcomprising: directing a beam steering antenna structure to generate oneor more radio frequency (RF) beams and radiate the one or more RF beamsto a surrounding environment; producing radar data from one or morereturn RF beams reflected from the surrounding environment; determiningparameters of the one or more RF beams during a guidance of a perceptionengine; detecting a moving object in a path of the surroundingenvironment from the radar data; controlling the beam steering of thebeam steering antenna structure based on the detection of the movingobject, wherein controlling includes focusing on a specific area of afield of view (FoV) within a scan angular range; determining whether themoving object in the path is violating directional criteria; and sendinga communication signal to one or more receiving units in the surroundingenvironment when the moving object in the path is violating thedirectional criteria, the communication signal indicating an alertmessage that notifies the one or more receiving units to perform a firstpreventative action that causes the one or more receiving units to avoidthe path of the moving object.
 16. The method of claim 15, furthercomprising: obtaining a velocity measurement of the moving object fromthe radar data; determining that the velocity measurement does notsatisfy the directional criteria; and generating the communicationsignal with a first priority that corresponds to the first preventativeaction.
 17. The method of claim 16, wherein determining that thevelocity measurement does not satisfy the directional criteria comprisesdetermining that the velocity measurement is lesser than zero.
 18. Themethod of claim 16, wherein determining that the velocity measurementdoes not satisfy the directional criteria comprises determining that thevelocity measurement is not within a first range of velocities, thefirst range of velocities comprising compliant velocities.
 19. Themethod of claim 16, further comprising determining that the velocitymeasurement corresponds to the first action from a mapping between aplurality of actions and velocity measurements of the moving object. 20.The method of claim 16, further comprising: confirming whether thevelocity measurement is lesser than zero, or within the first range ofvelocities; sending a second communication signal indicating a secondalert message with a second priority different from the first prioritywhen the velocity measurement is confirmed, the second alert messagecausing the one or more receiving units to perform a second action withmore urgency than the first action; and sending a third communicationsignal that instructs the one or more receiving units to cancel thefirst action when the velocity measurement is not confirmed.